INT 16 - PC Tools v8+ programs - GET ???

	AX = FE55h
	CX = segment of resident program or 0000h for last loaded
	DX = 0000h
Return: DX = resident code segment (unchanged if CX=0000h on entry)
	AX = ??? or 0000h
Note:	this call is supported by CPSCHED, CPTASK, DATAMON, DPROTECT, DRIVEMAP,
	  and DSKLIGHT beginning in PC Tools v8.0; programs other than CPTASK
	  seem to hook it merely to return the same AX as the CPTASK loaded
	  prior to them returned